A Review on the Respiratory System Toxicity of Carbon Nanoparticles

Nanoparticles and Airway Epithelial Cells: Exploring the Impacts and Methodologies in Toxicity Assessment

The production of nanoparticles has recently surged due to their varied applications in the biomedical, pharmaceutical, textile, and electronic sectors. However, this rapid increase in nanoparticle manufacturing has raised concerns about environmental pollution, particularly its potential adverse effects on human health. Among the various concerns, inhalation exposure to nanoparticles poses significant risks, especially affecting the respiratory system. Airway epithelial cells play a crucial role as the primary defense against inhaled particulate matter and pathogens. Studies have shown that nanoparticles can disrupt the airway epithelial barrier, triggering inflammatory responses, generating reactive oxygen species, and compromising cell viability. However, our understanding of how different types of nanoparticles specifically impact the airway epithelial barrier remains limited. Both in vitro cell culture and in vivo murine models are commonly utilized to investigate nanoparticle-induced cellular responses and barrier dysfunction. This review discusses the methodologies frequently employed to assess nanoparticle toxicity and barrier disruption. Furthermore, we analyze and compare the distinct effects of various nanoparticle types on the airway epithelial barrier. By elucidating the diverse responses elicited by different nanoparticles, we aim to provide insights that can guide future research endeavors in assessing and mitigating the potential risks associated with nanoparticle exposure.

The Effect of Rapeseed Oil Biopolyols and Cellulose Biofillers on Selected Properties of Viscoelastic Polyurethane Foams

This paper presents the results of research on polyurethane viscoelastic foams (PUVFs) modified with biomaterials. This investigation looked at the effect of the biomaterials on the foaming processes, as well as the acoustical and selected physical-mechanical properties of the foams. Various types of rapeseed oil biopolyols and microcellulose were used to modify the materials. The analysis of properties covered a reference biopolyol-free sample and materials containing 10 wt.%, 20 wt.%, and 30 wt.% of different types of biopolyols in the mixture of polyol components. The biopolyols differed in terms of functionality and hydroxyl value (OHv). Next, a selected formulation was modified with various microcellulose biofillers in the amount of 0.5-2 wt.%. The PUVFs, with apparent densities of more than 210 kg/m3 and open-cell structures (more than 85% of open cells), showed a slow recovery to their original shape after deformation when the pressure force was removed. They were also characterized by a tensile strength in the range of 156-264 kPa, elongation at break of 310-510%, hardness of 8.1-23.1 kPa, and a high comfort factor of 3.1-7.1. The introduction of biopolyols into the polyurethane system resulted in changes in sound intensity levels of up to 31.45%, while the addition of fillers resulted in changes in sound intensity levels of up to 13.81%.

Cell membrane-coated nanomaterials for cancer therapy

With the development of nanotechnology, nanoparticles have emerged as a delivery carrier for tumor drug therapy, which can improve the therapeutic effect by increasing the stability and solubility and prolonging the half-life of drugs. However, nanoparticles are foreign substances for humans, are easily cleared by the immune system, are less targeted to tumors, and may even be toxic to the body. As a natural biological material, cell membranes have unique biological properties, such as good biocompatibility, strong targeting ability, the ability to evade immune surveillance, and high drug-carrying capacity. In this article, we review cell membrane-coated nanoparticles (CMNPs) and their applications to tumor therapy. First, we briefly describe CMNP characteristics and applications. Second, we present the characteristics and advantages of different cell membranes as well as nanoparticles, provide a brief description of the process of CMNPs, discuss the current status of their application to tumor therapy, summarize their shortcomings for use in cancer therapy, and propose future research directions. This review summarizes the research progress on CMNPs in cancer therapy in recent years and assesses remaining problems, providing scholars with new ideas for future research on CMNPs in tumor therapy.

Application of Inorganic Nanomaterials in Cultural Heritage Conservation, Risk of Toxicity, and Preventive Measures

Nanotechnology has allowed for significant progress in architectural, artistic, archaeological, or museum heritage conservation for repairing and preventing damages produced by deterioration agents (weathering, contaminants, or biological actions). This review analyzes the current treatments using nanomaterials, including consolidants, biocides, hydrophobic protectives, mechanical resistance improvers, flame-retardants, and multifunctional nanocomposites. Unfortunately, nanomaterials can affect human and animal health, altering the environment. Right now, it is a priority to stop to analyze its advantages and disadvantages. Therefore, the aims are to raise awareness about the nanotoxicity risks during handling and the subsequent environmental exposure to all those directly or indirectly involved in conservation processes. It reports the human-body interaction mechanisms and provides guidelines for preventing or controlling its toxicity, mentioning the current toxicity research of main compounds and emphasizing the need to provide more information about morphological, structural, and specific features that ultimately contribute to understanding their toxicity. It provides information about the current documents of international organizations (European Commission, NIOSH, OECD, Countries Normative) about worker protection, isolation, laboratory ventilation control, and debris management. Furthermore, it reports the qualitative risk assessment methods, management strategies, dose control, and focus/receptor relationship, besides the latest trends of using nanomaterials in masks and gas emissions control devices, discussing their risk of toxicity.

Aerosolised micro and nanoparticle: formulation and delivery method for lung imaging

Purpose

The application of contrast and tracing agents is essential for lung imaging, as indicated by the wide use in recent decades and the discovery of various new contrast and tracing agents. Different aerosol production and pulmonary administration methods have been developed to improve lung imaging quality. This review details and discusses the ideal characteristics of aerosol administered via pulmonary delivery for lung imaging and the methods for the production and pulmonary administration of dry or liquid aerosol.

Methods

We explored several databases, including PubMed, Scopus, and Google Scholar, while preparing this review to discover and obtain the abstracts, reports, review articles, and research papers related to aerosol delivery for lung imaging and the formulation and pulmonary delivery method of dry and liquid aerosol. The search terms used were "dry aerosol delivery", "liquid aerosol delivery", "MRI for lung imaging", "CT scan for lung imaging", "SPECT for lung imaging", "PET for lung imaging", "magnetic particle imaging", "dry powder inhalation", "nebuliser", and "pressurised metered-dose inhaler".

Results

Through the literature review, we found that the critical considerations in aerosol delivery for lung imaging are appropriate lung deposition of inhaled aerosol and avoiding toxicity. The important tracing agent was also found to be Technetium-99m (^99mTc), Gallium-68 (⁶⁸Ga) and superparamagnetic iron oxide nanoparticle (SPION), while the essential contrast agents are gold, iodine, silver gadolinium, iron and manganese-based particles. The pulmonary delivery of such tracing and contrast agents can be performed using dry formulation (graphite ablation, spark ignition and spray dried powder) and liquid aerosol (nebulisation, pressurised metered-dose inhalation and air spray).

Conclusion

A dual-imaging modality with the combination of different tracing or contrast agents is a future development of aerosolised micro and nanoparticles for lung imaging to improve diagnosis success.

Graphical abstract

Polysaccharide-Based Nanomedicines Targeting Lung Cancer

A primary illness that accounts for a significant portion of fatalities worldwide is cancer. Among the main malignancies, lung cancer is recognised as the most chronic kind of cancer around the globe. Radiation treatment, surgery, and chemotherapy are some medical procedures used in the traditional care of lung cancer. However, these methods lack selectivity and damage nearby healthy cells. Several polysaccharide-based nanomaterials have been created to transport chemotherapeutics to reduce harmful and adverse side effects and improve response during anti-tumour reactions. To address these drawbacks, a class of naturally occurring polymers called polysaccharides have special physical, chemical, and biological characteristics. They can interact with the immune system to induce a better immunological response. Furthermore, because of the flexibility of their structures, it is possible to create multifunctional nanocomposites with excellent stability and bioavailability for the delivery of medicines to tumour tissues. This study seeks to present new views on the use of polysaccharide-based chemotherapeutics and to highlight current developments in polysaccharide-based nanomedicines for lung cancer.

A critical review on the role of abiotic factors on the transformation, environmental identity and toxicity of engineered nanomaterials in aquatic environment

Engineered nanomaterials (ENMs) are at the forefront of many technological breakthroughs in science and engineering. The extensive use of ENMs in several consumer products has resulted in their release to the aquatic environment. ENMs entering the aquatic ecosystem undergo a dynamic transformation as they interact with organic and inorganic constituents present in aquatic environment, specifically abiotic factors such as NOM and clay minerals, and attain an environmental identity. Thus, a greater understanding of ENM-abiotic factors interactions is required for an improved risk assessment and sustainable management of ENMs contamination in the aquatic environment. This review integrates fundamental aspects of ENMs transformation in aquatic environment as impacted by abiotic factors, and delineates the recent advances in bioavailability and ecotoxicity of ENMs in relation to risk assessment for ENMs-contaminated aquatic ecosystem. It specifically discusses the mechanism of transformation of different ENMs (metals, metal oxides and carbon based nanomaterials) following their interaction with the two most common abiotic factors NOM and clay minerals present within the aquatic ecosystem. The review critically discusses the impact of these mechanisms on the altered ecotoxicity of ENMs including the impact of such transformation at the genomic level. Finally, it identifies the gaps in our current understanding of the role of abiotic factors on the transformation of ENMs and paves the way for the future research areas.

Physical and chemical properties of carbon nanotubes in view of mechanistic neuroscience investigations. Some outlook from condensed matter, materials science and physical chemistry

The open border between non-living and living matter, suggested by increasingly emerging fields of nanoscience interfaced to biological systems, requires a detailed knowledge of nanomaterials properties. An account of the wide spectrum of phenomena, belonging to physical chemistry of interfaces, materials science, solid state physics at the nanoscale and bioelectrochemistry, thus is acquainted for a comprehensive application of carbon nanotubes interphased with neuron cells. This review points out a number of conceptual tools to further address the ongoing advances in coupling neuronal networks with (carbon) nanotube meshworks, and to deepen the basic issues that govern a biological cell or tissue interacting with a nanomaterial. Emphasis is given here to the properties and roles of carbon nanotube systems at relevant spatiotemporal scales of individual molecules, junctions and molecular layers, as well as to the point of view of a condensed matter or materials scientist. Carbon nanotube interactions with blood-brain barrier, drug delivery, biocompatibility and functionalization issues are also regarded.

Synergic effects of nanoparticles-mediated hyperthermia in radiotherapy/chemotherapy of cancer

The conventional cancer treatment modalities such as radiotherapy and chemotherapy suffer from several limitations; hence, their efficiency needs to be improved with other complementary modalities. Hyperthermia, as an adjuvant therapeutic modality for cancer, can result in a synergistic effect on radiotherapy (radiosensitizer) and chemotherapy (chemosensitizer). Conventional hyperthermia methods affect both tumoral and healthy tissues and have low specificity. In addition, a temperature gradient generates in the tissues situated along the path of the heat source, which is a more serious for deep-seated tumors. Nanoparticles (NPs)-induced hyperthermia can resolve these drawbacks through localization around/within tumoral tissue and generating local hyperthermia. Although there are several review articles dealing with NPs-induced hyperthermia, lack of a paper discussing the combination of NPs-induced hyperthermia with the conventional chemotherapy or radiotherapy is tangible. Accordingly, the main focus of the current paper is to summarize the principles of NPs-induced hyperthermia and more importantly its synergic effects on the conventional chemotherapy or radiotherapy. The heat-producing nanostructures such as gold NPs, iron oxide NPs, and carbon NPs, as well as the non-heat-producing nanostructures, such as lipid-based, polymeric, and silica-based NPs, as the carrier for heat-producing NPs, are discussed and their pros and cons highlighted.

The pulmonary toxicity of carboxylated or aminated multi-walled carbon nanotubes in mice is determined by the prior purification method

Background

Inhalation of multi-walled carbon nanotubes (MWCNTs) poses a potential risk to human health. In order to safeguard workers and consumers, the toxic properties of MWCNTs need to be identified. Functionalization has been shown to either decrease or increase MWCNT-related pulmonary injury, depending on the type of modification. We, therefore, investigated both acute and chronic pulmonary toxicity of a library of MWCNTs derived from a common pristine parent compound (NC7000).

Methods

MWCNTs were thermally or chemically purified and subsequently surface functionalized by carboxylation or amination. To evaluate pulmonary toxicity, male C57BL6 mice were dosed via oropharyngeal aspiration with either 1.6 or 4 mg/kg of each MWCNT type. Mitsui-7 MWCNT was used as a positive control. Necropsy was performed at days 3 and 60 post-exposure to collect bronchoalveolar lavage fluid (BALF) and lungs.

Results

At day 3 all MWCNTs increased the number of neutrophils in BALF. Chemical purification had a greater effect on pro-inflammatory cytokines (IL-1β, IL-6, CXCL1) in BALF, while thermal purification had a greater effect on pro-fibrotic cytokines (CCL2, OPN, TGF-β1). At day 60, thermally purified, carboxylated MWCNTs had the strongest effect on lymphocyte numbers in BALF. Thermally purified MWCNTs caused the greatest increase in LDH and total protein in BALF. Furthermore, the thermally purified and carboxyl- or amine-functionalized MWCNTs caused the greatest number of granulomatous lesions in the lungs. The physicochemical characteristics mainly associated with increased toxicity of the thermally purified derivatives were decreased surface defects and decreased amorphous content as indicated by Raman spectroscopy.

Conclusions

These data demonstrate that the purification method is an important determinant of lung toxicity induced by carboxyl- and amine-functionalized MWCNTs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12989-020-00390-y.

Organ-on-a-chip platforms for accelerating the evaluation of nanomedicine

Nanomedicine involves the use of engineered nanoscale materials in an extensive range of diagnostic and therapeutic applications and can be applied to the treatment of many diseases. Despite the rapid progress and tremendous potential of nanomedicine in the past decades, the clinical translational process is still quite slow, owing to the difficulty in understanding, evaluating, and predicting nanomaterial behaviors within the complex environment of human beings. Microfluidics-based organ-on-a-chip (Organ Chip) techniques offer a promising way to resolve these challenges. Sophisticatedly designed Organ Chip enable in vitro simulation of the in vivo microenvironments, thus providing robust platforms for evaluating nanomedicine. Herein, we review recent developments and achievements in Organ Chip models for nanomedicine evaluations, categorized into seven broad sections based on the target organ systems: respiratory, digestive, lymphatic, excretory, nervous, and vascular, as well as coverage on applications relating to cancer. We conclude by providing our perspectives on the challenges and potential future directions for applications of Organ Chip in nanomedicine.

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Microfluidics-based organ-on-a-chip (Organ Chip) techniques offer a promising way to understand, evaluate, and predict nanomedicine behaviors within the complex environment.

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Organ Chip models for nanomedicine evaluations are categorized into seven broad sections based on the targeted body systems.

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Limitations, challenges, and perspectives of Organ Chip for accelerating the assessment of nanomedicine are discussed, respectively.

Carbon Nanomaterials Promote M1/M2 Macrophage Activation

Toxic effects of certain carbon nanomaterials (CNM) have been observed in several exposure scenarios both in vivo and in vitro. However, most of the data currently available has been generated in a high-dose/acute exposure setup, limiting the understanding of their immunomodulatory mechanisms. Here, macrophage-like THP-1 cells, exposed to ten different CNM for 48 h in low-cytotoxic concentration of 10 µg mL^-1 , are characterized by secretion of different cytokines and global transcriptional changes. Subsequently, the relationships between cytokine secretion and transcriptional patterns are modeled, highlighting specific pathways related to alternative macrophage activation. Finally, time- and dose-dependent activation of transcription and secretion of M1 marker genes IL-1β and tumor necrosis factor, and M2 marker genes IL-10 and CSF1 is confirmed among the three most responsive CNM, with concentrations of 5, 10, and 20 µg mL^-1 at 24, 48, and 72 h of exposure. These results underline CNM effects on the formation of cell microenvironment and gene expression leading to specific patterns of macrophage polarization. Taken together, these findings imply that, instead of a high and toxic CNM dose, a sub-lethal dose in controlled exposure setup can be utilized to alter the cell microenvironment and program antigen presenting cells, with fascinating implications for novel therapeutic strategies.

Evaluating performance, degradation, and release behavior of a nanoform pigmented coating after natural and accelerated weathering

Pigments with nanoscale dimensions are added to exterior coatings to achieve desirable color and gloss properties. The present study compared the performance, degradation, and release behavior of an acrylic coating that was pigmented by a nanoform of Cu-phthalocyanine after both natural (i.e., outdoor) and accelerated weathering. Samples were weathered outdoors in three geographically distinct locations across the United States (Arizona, Colorado, Maryland) continuously for 15 months. Identically prepared samples were also artificially weathered under accelerated conditions (increased ultraviolet (UV) light intensity and elevated temperatures) for three months, in one-month increments. After exposure, both sets of samples were characterized with color, gloss, and infrared spectroscopy measurements, and selectively with surface roughness measurements. Results indicated that UV-driven coating oxidation was the principal degradation pathway for both natural and accelerated weathering samples, with accelerated weathering leading to an increased rate of oxidation without altering the fundamental degradation pathway. The inclusion of the nanoform pigment reduced the rate of coating oxidation, via UV absorption by the pigment, leading to improved coating integrity compared to non-pigmented samples. Release measurements collected during natural weathering studies indicated there was never a period of weathering, in any location, that led to copper material release above background copper measurements. Lab-based release experiments performed on samples weathered naturally and under accelerated conditions found that the release of degraded coating material after each type of exposure was diminished by the inclusion of the nanoform pigment. Release measurements also indicated that the nanoform pigment remained embedded within the coating and did not release after weathering.

Evaluating performance, degradation, and release behavior of a nanoform pigmented coating after natural and accelerated weathering

Pigments with nanoscale dimensions are added to exterior coatings to achieve desirable color and gloss properties. The present study compared the performance, degradation, and release behavior of an acrylic coating that was pigmented by a nanoform of Cu-phthalocyanine after both natural (i.e., outdoor) and accelerated weathering. Samples were weathered outdoors in three geographically distinct locations across the United States (Arizona, Colorado, Maryland) continuously for 15 months. Identically prepared samples were also artificially weathered under accelerated conditions (increased ultraviolet (UV) light intensity and elevated temperatures) for three months, in one-month increments. After exposure, both sets of samples were characterized with color, gloss, and infrared spectroscopy measurements, and selectively with surface roughness measurements. Results indicated that UV-driven coating oxidation was the principal degradation pathway for both natural and accelerated weathering samples, with accelerated weathering leading to an increased rate of oxidation without altering the fundamental degradation pathway. The inclusion of the nanoform pigment reduced the rate of coating oxidation, via UV absorption by the pigment, leading to improved coating integrity compared to non-pigmented samples. Release measurements collected during natural weathering studies indicated there was never a period of weathering, in any location, that led to copper material release above background copper measurements. Lab-based release experiments performed on samples weathered naturally and under accelerated conditions found that the release of degraded coating material after each type of exposure was diminished by the inclusion of the nanoform pigment. Release measurements also indicated that the nanoform pigment remained embedded within the coating and did not release after weathering.

Excitons in Carbonic Nanostructures

Unexpectedly bright photoluminescence emission can be observed in materials incorporating inorganic carbon when their size is reduced from macro–micro to nano. At present, there is no consensus in its understanding, and many suggested explanations are not consistent with the broad range of experimental data. In this Review, I discuss the possible role of collective excitations (excitons) generated by resonance electronic interactions among the chromophore elements within these nanoparticles. The Förster-type resonance energy transfer (FRET) mechanism of energy migration within nanoparticles operates when the composing fluorophores are the localized electronic systems interacting at a distance. Meanwhile, the resonance interactions among closely located fluorophores may lead to delocalization of the excited states over many molecules resulting in Frenkel excitons. The H-aggregate-type quantum coherence originating from strong coupling among the transition dipoles of adjacent chromophores in a co-facial stacking arrangement and exciton transport to emissive traps are the basis of the presented model. It can explain most of the hitherto known experimental observations and must stimulate the progress towards their versatile applications.

Three-Dimensional Quantitative Co-Mapping of Pulmonary Morphology and Nanoparticle Distribution with Cellular Resolution in Nondissected Murine Lungs

Deciphering biodistribution, biokinetics, and biological effects of nanoparticles (NPs) in entire organs with cellular resolution remains largely elusive due to the lack of effective imaging tools. Here, light sheet fluorescence microscopy in combination with optical tissue clearing was validated for concomitant three-dimensional mapping of lung morphology and NP biodistribution with cellular resolution in nondissected ex vivo murine lungs. Tissue autofluorescence allowed for label-free, quantitative morphometry of the entire bronchial tree, acinar structure, and blood vessels. Co-registration of fluorescent NPs with lung morphology revealed significant differences in pulmonary NP distribution depending on the means of application (intratracheal instillation and ventilator-assisted aerosol inhalation under anesthetized conditions). Inhalation exhibited a more homogeneous NP distribution in conducting airways and acini indicated by a central-to-peripheral (C/P) NP deposition ratio of unity (0.98 ± 0.13) as compared to a 2-fold enhanced central deposition (C/P = 1.98 ± 0.37) for instillation. After inhalation most NPs were observed in the proximal part of the acini as predicted by computational fluid dynamics simulations. At cellular resolution patchy NP deposition was visualized in bronchioles and acini, but more pronounced for instillation. Excellent linearity of the fluorescence intensity-dose response curve allowed for accurate NP dosimetry and revealed ca. 5% of the inhaled aerosol was deposited in the lungs. This single-modality imaging technique allows for quantitative co-registration of tissue architecture and NP biodistribution, which could accelerate elucidation of NP biokinetics and bioactivity within intact tissues, facilitating both nanotoxicology studies and the development of nanomedicines.

Carbon nanotubes and central nervous system: Environmental risks, toxicological aspects and future perspectives

Due to their morphological and physicochemical properties, carbon nanotubes (CNTs) enhance the structural properties of several materials and are produced in great volumes. The production and the manufacturing of CNTs-incorporated products can lead to the potential environmental release of CNTs. For these reasons, CNTs can represent a serious concern for human health. Humans are exposed to nanoparticles through inhalation, ingestion and skin uptake. After their entrance, the particles can reach the Central Nervous System (CNS) through three different pathways: the systemic, olfactory and trigeminal pathways. In the first, through systemic blood circulation, nanoparticles cross both the blood-brain and blood-spinal cord barriers, which are highly selective semipermeable barriers that protect the CNS compartments. The second is the step from the nose to brain route and occurs along axons and via nerve bundles that cross the cribriform plate to the olfactory bulb. In the third, the compounds diffuse through the nasal cavity mucosa to reach the branches of the trigeminal nerve in the olfactory and respiratory regions, and they reach brain stem via axonal transport. After their entrance, CNTs reach the CNS where they may cause cytotoxicity of selected neurons in several CNS regions, impairing molecular pathways and contributing to the onset and progression of chronic brain inflammation, microglia activation and white matter abnormalities with an increased risk for autism spectrum disorders, lower IQ in children, neurodegenerative diseases and stroke. The large surface area to mass ratio of CNTs greatly increases surface reactivity. Despite this property considerable contributes to their toxicological profile in biological systems, also makes CNTs very attractive in the medical field, where they can be used as carriers of bioactive molecules, contrast agents, biological platforms and for many other applications in medicine.

Proteomic investigation on bio-corona of functionalized multi-walled carbon nanotubes

BACKGROUND

The formation of bio-corona, due to adsorption of biomolecules onto carbon nanotubes (CNTs) surface in a physiological environment, may lead to a modified biological "identity" of CNTs, contributing to determination of their biocompatibility and toxicity.

METHODS

Multi-walled carbon nanotubes surfaces (f-MWCNTs) were modified attaching acid and basic chemical functions such as carboxyl (MWCNTs-COOH) and ammonium (MWCNTs-N) groups respectively. The investigation of interactions between f-MWCNTs and proteins present in biological fluids, like human plasma, was performed by electrophoretic separation (SDS-PAGE) and mass spectrometry analysis (nLC-MS/MS).

RESULTS

A total of 52 validated proteins was identified after incubation of f-MWCNTs in human plasma. 86% of them was present in bio-coronas formed on the surface of all f-MWCNTs and 29% has specifically interacted with only one type of f-MWCNTs.

CONCLUSIONS

The evaluation of proteins primary structures, present in all bio-coronas, did not highlight any correlation between the chemical functionalization on MWCNTs and the content of acid, basic and hydrophobic amino acids. Despite this, many proteins of bio-corona, formed on all f-MWCNTs, were involved in the inhibitor activity of serine- or cysteine- endopeptidases, a molecular function completely unrevealed in the human plasma as control. Finally, the interaction with immune system's proteins and apolipoproteins has suggested a possible biocompatibility and a favored bio-distribution of tested f-MWCNTs.

GENERAL SIGNIFICANCE

Considering the great potential of CNTs in the nanomedicine, a specific chemical functionalization onto MWCNTs surface could control the protein corona formation and the biocompatibility of nanomaterials.

Thrombospondin-1 and microRNA-1 expression in response to multiwalled carbon nanotubes in alveolar epithelial cells

Thrombospondin-1 (TSP-1) is a glycoprotein that plays a role in extracellular matrix (ECM) remodeling. Previously, we have shown that multiwalled carbon nanotubes (MWCNT) regulate ECM components TGFβ and its target Col3A1 in alveolar epithelial cells. In this study, we investigated the effect of MWCNT on TSP-1 and microRNA-1 (miR-1) in the regulation of TGFβ in ECM remodeling using alveolar epithelial A549 cells. A549 cells were treated with MWCNT (20 or 50 µg/mL) for 6 or 24 h and the expression of TSP-1 and miR-1, and the exogenous miR-1 effect on cell morphology were analyzed. MWCNT induced in a time- and dose-dependent manner the expression of TSP-1. miR-1 was suppressed by MWCNT after 6 or 24 h of treatment regardless of the dose. TSP-1 and miR-1 negatively correlated with each other, r = -0.58. Exogenous administration of miR-1 induced alveolar epithelial cell morphology changes including cell clustering, whereas inhibition of miR-1 induced less cell to cell contact, cell rounding, and cellular projections. IntAct molecular network interactions analysis revealed that TSP-1 interacts with 21 molecular factors including ECM genes, and molecules. These results indicate a relationship between that TSP-1, MWCNT, and TGFβ, and suggest TSP-1 may play a role in MWCNT-induced TGFβ and ECM remodeling. Moreover, these data also suggest an inverse relationship between TSP-1 and miR-1 and a potential role of miR-1 in MWCNT-induced fibrotic signaling. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1596-1606, 2017.

Experimental-Computational Study of Carbon Nanotube Effects on Mitochondrial Respiration: In Silico Nano-QSPR Machine Learning Models Based on New Raman Spectra Transform with Markov-Shannon Entropy Invariants

The study of selective toxicity of carbon nanotubes (CNTs) on mitochondria (CNT-mitotoxicity) is of major interest for future biomedical applications. In the current work, the mitochondrial oxygen consumption (E3) is measured under three experimental conditions by exposure to pristine and oxidized CNTs (hydroxylated and carboxylated). Respiratory functional assays showed that the information on the CNT Raman spectroscopy could be useful to predict structural parameters of mitotoxicity induced by CNTs. The in vitro functional assays show that the mitochondrial oxidative phosphorylation by ATP-synthase (or state V3 of respiration) was not perturbed in isolated rat-liver mitochondria. For the first time a star graph (SG) transform of the CNT Raman spectra is proposed in order to obtain the raw information for a nano-QSPR model. Box-Jenkins and perturbation theory operators are used for the SG Shannon entropies. A modified RRegrs methodology is employed to test four regression methods such as multiple linear regression (LM), partial least squares regression (PLS), neural networks regression (NN), and random forest (RF). RF provides the best models to predict the mitochondrial oxygen consumption in the presence of specific CNTs with R² of 0.998-0.999 and RMSE of 0.0068-0.0133 (training and test subsets). This work is aimed at demonstrating that the SG transform of Raman spectra is useful to encode CNT information, similarly to the SG transform of the blood proteome spectra in cancer or electroencephalograms in epilepsy and also as a prospective chemoinformatics tool for nanorisk assessment. All data files and R object models are available at https://dx.doi.org/10.6084/m9.figshare.3472349 .

Graphene oxide nanosheets induced genotoxicity and pulmonary injury in mice

Graphene and graphene-related materials have broadly applied in biomedical purposes due to their unique properties, thus safety evaluation of them is crucial. This study was performed to explore the genotoxic and pulmonary toxic potential of different doses of graphene oxide nanosheets' (GOs) in mice.A total of 90 male mature mice were randomly divided into six groups of fifteen mice per each, five groups were intraperitoneally injected by GO at doses of 10, 50, 100, 250 and 500μg/kg b.w once weekly in addition to the control group that was injected intraperitoneally with 0.2ml saline solution. Five animals from each group were euthanized after 7, 28 and 56days post treatment. Evaluation of genotoxicity was performed through detection of chromosomal aberrations in bone marrow while assessment of lung injury was made by determination of DNA fragmentation in lung specimens using the alkali Comet assay, pulmonary oxidative markers estimation and finally histopathological investigations. Results revealed that GOs induced variable structural chromosomal aberrations (SCA) in bone marrow and DNA damage of lung cells that were time and dose dependent and represented by increase in%DNA in comet tail, tail moment and tail length and decrease in% head DNA in nuclei of lung of GOs-treated mice versus control groups in addition, GOs induced various changes in pulmonary oxidative stress parameters that were affected by dose and duration of treatment compared with the control as well as various pulmonary histopathological alterations were detected indicating lung injury.

CONCLUSION

GO potentiate the induction of genotoxicity and pulmonary injury in mice in time and dose dependent manner.

New insights on 'old' toxicants in occupational toxicology (Review)

In order to deliver the best possible working environment, it is essential to identify professional conditions that could be harmful for worker's health and prevent (or limit) the occurrence of such conditions. The appropriate use of personal protective equipment and the development of appropriate regulations allowed to reduce the prevalence of 'classic' occupational diseases, such as occupational hearing loss or asbestosis, just to name a few. Nowadays, environmental pollution seems to be one of the most relevant concerns for human and animal health, and toxicology is becoming one of the most prominent fields of interest in occupational settings. An increasing number of studies demonstrate that the presence of toxicants in the workplace could be responsible for the development of chronic diseases, even at doses that were considered 'safe'. The present review summarizes some of the most recent advancements in occupational toxicology, focusing on topics that have long been debated in the past and that have recently returned to the fore.

Nano-Inclusions Applied in Cement-Matrix Composites: A Review

Research on cement-based materials is trying to exploit the synergies that nanomaterials can provide. This paper describes the findings reported in the last decade on the improvement of these materials regarding, on the one hand, their mechanical performance and, on the other hand, the new properties they provide. These features are mainly based on the electrical and chemical characteristics of nanomaterials, thus allowing cement-based elements to acquire "smart" functions. In this paper, we provide a quantitative approach to the reinforcements achieved to date. The fundamental concepts of nanoscience are introduced and the need of both sophisticated devices to identify nanostructures and techniques to disperse nanomaterials in the cement paste are also highlighted. Promising results have been obtained, but, in order to turn these advances into commercial products, technical, social and standardisation barriers should be overcome. From the results collected, it can be deduced that nanomaterials are able to reduce the consumption of cement because of their reinforcing effect, as well as to convert cement-based products into electric/thermal sensors or crack repairing materials. The main obstacle to foster the implementation of such applications worldwide is the high cost of their synthesis and dispersion techniques, especially for carbon nanotubes and graphene oxide.